f they see the future, for which there is only one, than it doesn't follow at all that they'd see any but one of many choices.

It's hard to know what something that does not exist would see.
If there is one future, there are many choices in that future. I don't exactly follow your logic. Can you help me out? :?

Ok.

Let's say I can see events in the future very well. I've accurately predicted big earthquakes, volcanoes and key events in other's lives. With enough of an accurate record most people would call me psychic. It would make no difference if I couldn't see the route or decisions to get to that snap shot of the future that I predict. I would make no difference if I couldn't see possible alternatives because ultimately there is only one future, and that's the one I could see.

I predict someone will die in a car accident next Saturday. Like some bad sci-fi it doesn't matter how he tries to avoid it, he will somehow end up in a car and be killed. I'd hope of course that he'd do something useful though, like perhaps update his Will from the sex machine he met on his last Vegas fling four years ago to his current wife.

If thre were phsycics they would be able to forsee anything, regardless of anything. Phsycics see the future, so yes, they would see all the choices.

Nobody can predict what they actually know. It is not a prediction if one can see the future. So I think we can eliminate prediction as a psychic ability. The ability would be to see the future.

Much of seeing the future depends on having a future to see. IOW future events would have already happened and as such they already exist somewhere. I think we've been down this road before.

So much of what psychics do (or don't do) proves they can't see the future. Every future knowing psychic today should not even need to get into the foretelling business. Simply put next week's lottery numbers on a ticket, go to the prize office and wait for it to open the day after the draw. Psychics who know the future don't even need to witness the actual draw, just head to the nearest cashier. If that isn't your style then buy stock.

You have to feel sorry for those who finally realize their ability only to discover they are going to die in the next couple hours. People don't visit psychics to just know the future, they need to know in case they want to change it. How can you change the known future?

All that belongs to human understanding, in this deep ignorance and obscurity, is to be skeptical, or at least cautious; and not to admit of any hypothesis, whatsoever; much less, of any which is supported by no appearance of probability...Hume

Deja vu, well known yet i still have to explain it several times a month. Now how often don't you have a feeling you know exactly what is going to happen. A lot of these psychics are either a. believing they actually do see the future coincidence, or b. they want others to believe they do.

Now as for the contradiction between foresight and free will. If one believes in foresight there are numerous ways to find a solution to the problems that might arise.

The trouble with seeing the future is that the line between the observer and the thing-to-be-observed gets crossed. In order to know whether a certain bus is going to crash at 5pm today, you also need to know whether you are going to stop it from crashing. But... how do you know if you want to stop it until you know there's something to stop?

I think the answer is that you have to make up your mind about what you're going to do before you look. And... that... makes..... foreknowledge kind of useless.....

Some clocks are only right twice a day, but they are still right when they are right.

According to special relativity, if a person could travel at the speed of light and they could observe a person not traveling at that speed, then the person travelling at the speed of light would see the person at sublight's speed's life fly by and all the decisions that person made.

But is that observing the future ? in the above mentioned situation the person traveling at light speed is in a thus altered state that the person not traveling is actually moving forward in the normal space / time continuum. Also the person traveling at light speed is not seeing something that hasn't yet happened, he is just in a different state, since for him to see the future he would have to be able to return to the point where the person not traveling at light speed would be back at the time before his life unfolded.